package/waffle: new package

package/waffle: new package

waffle has four "backends", each having their own dependencies.
At least one "backend" must be enabled, otherwise Waffle will refuse to
build. The "backends" are:

 - glx, which needs full OpenGL + x11-xcb
 - wayland, which needs wayland-client, wayland-egl and EGL
 - x11-egl, which needs x11-xcb and EGL
 - gbm, which needs gbm, libudev and EGL

Backport an upstream patch fixing a build issue with musl toolchains.
Add a new patch fixing build with Wayand without X11.

Signed-off-by: Romain Naour <romain.naour@gmail.com>
[Thomas: drop GLES dependency, it is not mandatory.]
Signed-off-by: Thomas Petazzoni <thomas.petazzoni@bootlin.com>